Endoscopes are useful for diagnostic and therapeutic indications. They have been optimized to improve performance for particular purposes. Thus, there are endoscopes for examination of esophagus, stomach, duodenum and the like. Colonoscopes are specialized for examining the colon. Cystoscopes are specialized for examining the bladder, urethra and kidneys. Angioscopes are specialized for examining blood vessels. Bronchoscopes are specialized for examining the bronchi. Laproscopes are specialized for examining the peritoneal cavity. Arthroscopes are specialized for examining joint spaces. All of these devices are endoscopes. The devices generally are expensive and used in a contaminated environment. Thus, they are not one use devices and must be sterilized between uses so as not to spread contamination such as, for example, infection or disease.
It has been known to use sheath devices providing detachable covers for the viewing tube of the endoscope that is inserted into a body cavity. U.S. Pat. No. 6,911,005 describes a detachable sheath having an inner diameter smaller than the outer diameter of the viewing tube for an endoscope having an air feeding tube that is used to feed air into the sheath for inserting the viewing tube into the sheath. It also describes sheaths having an inner diameter larger than the outer diameter of the viewing tube. The viewing tube is inserted into the sheath device which is stretched over the viewing tube to reduce the diameter of the sheath device.
U.S. Pat. No. 4,646,722 discloses creating a variety of specialized endoscopes by using protective sheaths having various special purpose medical instruments mounted at the end of a biopsy channel and operated through the channel. U.S. Pat. No. 7,081,097 discloses a sheath assembly adapted for use with an endoscopic viewing tube where the sheath has a biopsy sampling device attached to the sheath including a collection member proximate the end.
U.S. Pat. No. 4,991,565 discloses providing an endoscope with a sheath that is removably fitted over the viewing tube and appears to have a plurality of channels for passing fluids provided within the sheath, each channel having an opening on at one end near the distal end portion of the sheath and extending at the other end past the proximal end of the sheath.
U.S. Pat. No. 6,793,661 discloses an endoscopic sheath having an inflatable member coupled to and surrounding a portion of the sheath body and adapted to be inflated radially. The sheath assembly further includes an expansion-inhibiting mechanism coupled to at least one of the inflatable member and the sheath body portion. The expansion-inhibiting mechanism inhibits longitudinal expansion of the sheath body portion during inflation of the inflatable member. Optionally, the sheath assembly may include a channel that extends longitudinally along the outer surface of the sheath body portion.
U.S. Pat. No. 8,845,518 discloses apparatus and methods for attaching and forming enclosed inflatable members on an endoscope assembly with a disposable sheath. A flexible and resilient cuff is fixed on the outer surface of the disposable sheath to form an annular space for inflation through a lumen internal to the sheath.
U.S. 2003/0114732 discloses a sheath for use with intracorporeal optical imaging instruments such as imaging guidewires, catheters or endoscopes. Also disclosed are sheath devices having multiple lumens longitudinally attached to each other at an exterior portion of the lumens.
U.S. 2007/0270646 discloses a disposable sheath for use with a cystoscope or endoscope. In one aspect of the disclosure the sheath includes an exterior wall and has a first channel and a second channel within the exterior wall of the sheath.
Although disposable sheaths have been known and used for some time, it appears that they have been designed and adapted for specific endoscopes by respective endoscope manufacturers. Indeed each type of endoscope may have slightly different measurements. It would be desirable to have a disposable sheath system that is adapted to be used on more than one manufacturer's endoscope for the particular type of endoscope such as, for example, a ureteroscope. Such a disposable sheath can be more economical and avoid the necessity for suppliers to store various disposable sheaths to fit the various endoscopes made by different manufacturers.